What's in-store for Diana on "The Secret Circle"? Party planning, getting all hopped up on Devil's Spirit, moving on from Adam and siding with Cassie when John Blackwell creates division within the high school witch group, for starters. Speaking to Hollywood Crush by phone, Shelley Hennig told us all about her character's arc over the next few episodes, her new castmates and her recent private hip-hop dance class.

This week's episode of "The Secret Circle," Episode 13 ("Medallion"), finds Diana helping to organize a birthday party for her ex. "Diana has been a planner for years. She loves parties and she loves Adam," Shelley explained. "She knows it's Adam's birthday. It's on the top of her head, trying to figure out if she should even do anything for him. She has been planning things for him for years, so how would she all of a sudden stop?

"Diana made a mature decision to give Adam the room to explore things with Cassie," she continued. "That being said, she still has a good relationship with Adam, if not an easy one. This is where [Adam's dad] Ethan comes in and asks Diana for help. It's kind of perfect in a perfectly awkward way. She can say, 'Well, your father asked me, so I couldn't say 'no' if she has to... The party will be fun. There's a really good scene."

Like Diana, Shelley enjoys a good party. She's addicted to the reality show "Dance Moms." After hearing her talk about it, new cast-member Tim Phillips (who reportedly will play "a mysterious rich kid") organized some private dance lessons for some of the actors. "I met Tim a few days ago. I'm all smiles. He's been fantastic. He's such a great guy, adorably handsome and a really good actor. I can't wait to see where [his character] goes... I was talking about 'Dance Moms' and the next thing I know, at 4 o'clock on Sunday, he's got a bunch of us at a private hip-hop class!"

Tim, of course, isn't the only new cast member. Joe Lando is set to appear in Episode 15 as Cassie's father, John Blackwell. "Joe is awesome! He's mysterious looking, which is perfect for his character, because let's face it: the Circle is still trying to figure out why he's back, what he wants and what his intentions are. Diana is really intrigued by him. All she's ever wanted to know is more about her mother. And here's Cassie with her father back after 16 years. You'll see some bickering between the Circle. We all have different opinions about whether we should trust him."

And where will Diana's opinion fall? "Diana is on Cassie's side," Shelley said.

Hmm, yes, Diana seems to side with Cassie on the regular. Why is that? We know that Blackwell has another kid running around. Could it be that Diana is, in fact, the Secret Sibling? "Everyone is a possibility," Shelley said. "If it's Diana, it would explain her connection with Cassie. When she breaks up with Adam, the first person she goes to is Cassie, even though Cassie is the reason they had to break up."

Whether he's her biological father or not, Charles is Diana's daddy right now. While nothing is on the horizon for the immediate future, Shelley seemed sure that sooner or later, the writers will explore their relationship even further. "I have the best father on television, don't I? Badass!

"You've seen Charles feeling remorse after he's killed people. I think it's inevitable for [the writers] to explore more about that. Is Diana ever going to find out that her father killed Cassie's mother? My fingers are crossed for them to explore that more!"

Whether Diana can ever truly move on from Adam, Episode 14 is called "Valentine," so perhaps love will be in the air for someone.

"Diana decides to move on—not necessarily with another person, but she's more like, 'I'm not going to focus on this Adam thing, I'm going to just move forward as much as I possibly can.'" Part of that process involves heading over to Faye's and an anti-Valentine's Day party. Melissa sees how badly Diana needs to relax, so she's all too happy to provide some of that treacherous Devil's Spirit to get the party started.

"Diana really lets loose in that episode and Shelley got to as well!" Shelley teased. "That was so fun! I'm kind of petrified to see it air, because I really went for it. You'll definitely see more comedy from me and Diana, so that'll be fun. Or at least that's what I've been told! I was on Devil's Spirit, so what can you possibly remember... I think Diana has a little too much fun with it."

What are your hopes and dreams for Diana? Sound off in the comments and on Twitter!